Lotus Elan and Lotus Elan Plus 2 Forums

Hello all

I have just spent yet another small fortune on my 71 + 2S130 4. I have just had her serviced (as I do every six months), had some suspension arms replaced, had a few switches fixed and been given an MOT.

The mechanic pointed out that the sharp cracking noise that I keep hearing when I change gear is not just the fibre glass body twisting as I have been told in the past. It is in fact worn out splines on the rear drive shaft! I am no mechanic so apologies if I have made a mistake with the terms.

Has anyone heard of this?

Is it going to another massively expensive repair? The mechanic said that it was fine to keep driving it till it breaks and that the action of it actually breaking would not damage the car further. Naturally - I have no intention of doing this as clearly it is not a good idea - but is this true?

Where am I going to get a new part from & how much is it?

Lots of questions and doubtless lots of money. While the "lots of trouble- etc" expression is coming true for me - I have no intention of giving up! those sunny days on country roads are worth every penny.

All help and advice gratefully received.

Rich

I think you need a new mechanic.
Chris

Hi

I will second that. I am not saying that I know what the noise is, but I am pretty sure that it is not that!

All the best

Rich ! - do not (!!) wait until you have an accident ! Do a full control of your driveline and find out ! When you say splines, I guess you mean the short stub axels into your diff. If they snap, you may damage yr diff internals. Much easier and cheaper to do it up front!

Dag

Actually I think this means the splined hub for the wheels. It may well be this causing the noise if they're slipping. (or am I wrong?). If it's this, obviously it cannot cause the driveshafts to split..

Thor
(hei Dag Henning!.)

The hub has a single key about an inch long and 1/8 inch in diameter. There are no splines.
The hub fits onto the outer driveshaft on a taper and is held in place by a large washer & nut. Take the wheel off and have a look, you'll see the nut I'm talking about. This may be loose (ish) allowing the drive shaft to turn inside the hub slightly, which may be causing the cracking noise. The nut has a high torque. Make sure this is tight. (I'll check the manual tonight for the torque setting and post it).
(I have just bought a new outer driveshaft because my old one was damaged. D'shaft and bearings were about ?250. Hope to fit them this weekend.)

If there is atill a cracking noise after you've done this then it may be the output shaft from the diff but I doubt it. There are many other components in the drive train that could make a cracking noise.
Does the cracking noise "just come from the back" or from one rear corner? That may give a clue.

I agree with the others - get yourself a new mechanic. A broken driveshaft is not funny and can cause a hell of a lot of damage.

Regards,

Hamish.

Rich

Could just be the propshaft uj's


regards

Ian

Sorry, aren't the single nut (or spinner) wheels pushed onto a splined shaft?

Excuse my ignorance for only having my +2S for a week and being used to my (now sold) TR4A with wire wheels and spinners thinking it's the same..

richardhallett99 wrote: It is in fact worn out splines on the rear drive shaft! I am no mechanic .
Has anyone heard of this?
Is it going to another massively expensive repair?
Where am I going to get a new part from & how much is it?
Rich

I think you must first find out what type of drive shafts are fitted, could be standard Doughnuts, one Doughnut and a C.V.joint, Two C.V.joints, hook joints/uj's with sliding splines or something else, ask you "mechanic" or somebody with some mechanical knowledge what you have fitted.
"Cracking noise with body twist"?????? something is wrong!
Brian

<i>"Sorry, aren't the single nut (or spinner) wheels pushed onto a splined shaft?"</i>

No. Look at the front of your own wheels you will see five pegs. These are the drive pegs which Lotus used rather than splines.

aha! So the wheelnuts/spinners should be tightened properly then, not like on my previous centre lock wires on the rattly Triumph?

thor

I think we can all agree on new mechanic,just in case there is a problem in drive train someone has parts on ebay under classic car parts look at lotus list does noise occur on over-run and accelaration?
Have fun Curly

the mechanic goes..... do you have another?
The "drive shaft" goes from the trans to the rear end.
"Halfshafts" go from the rear end to the wheels and have rotoflexes on each end.
When you say cracking, is it sharp like something being broken?

1964 S1 wrote:
The "drive shaft" goes from the trans to the rear end.
"Halfshafts" go from the rear end to the wheels and have rotoflexes on each end.

Thats just a matter of terminology, the Lotus Workshop Manual refers to the "halfshafts" as "intermediate drive shafts" and the "drive shaft" as the "propeller "shaft"
I think we all have our own way of describing a component and I would describe an open shaft as a "drive shaft" and an enclosed shaft (as in a solid rear axle) as a halfshaft but that is just me.
Brian

It's like that because there are also the "outboard drive shafts" and the "inboard drive shafts"

The early service manuals (not sure about the later ones) also refer to the intermediates as "fixed length drive shafts" - I thought they all were!